Curses! sorry about that, Should the client stand on their rights to use you instead of XYZ cleaning, you run the risk of a sabotaged job.
Insurance companies like large market /high street presences, and they will screw you right down to the bone on fees, I have seen unethical practices employed by companies trying to make a profit from it.
Your best course would be to contact local Loss Adjusting firms and introduce yourself. Good LAs manage claims personally, so you can build a real relationship with your contact and potential future clients, and get around £65+VAT a time for writing a letter saying "Yup, the carpet is shag (ged)." when the job really is a no-goer. I worked for Royal and Scum Alliance, who now advertise as "More Th>n"
Hope this helps.
Bill